/// <summary>
/// 用指定的对象类型创建<see cref="IMultiOutput"/>对象。
/// </summary>
/// <param name="elementType">目标元素类型。</param>
/// <param name="reader">数据库访问<see cref="DbDataReader"/>对象。</param>
/// <returns>查询输出对象。</returns>
private IMultiOutput CreateOutput(Type elementType, DbDataReader reader)
{
if (elementType.IsPrimary())
return new MultiValueOutputInfo();
else if (elementType.IsObject())
return new CollectionOutputInfo(reader, _Metadata.Type(elementType));
throw new NotSupportedException(string.Format(Res.NotSupportedOutpputClrType, elementType));
}
